Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering safety. The description adds value by listing the return fields (ID, name, path, description, star count, URL), giving the agent an expectation of the response shape beyond annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two sentences long, front-loaded with the main purpose, includes return details, and directly points to the alternative tool. Every sentence is useful and there is zero redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The tool is simple and the description covers its core purpose, return values, and relationship to a sibling. An output schema exists, so detailed return types are not needed in the description. However, it could mention pagination behavior or that 'all accessible' might imply a long list, but the schema's per_page parameter handles that.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage with all four parameters clearly documented. The description adds no additional parameter-level meaning beyond what the schema already provides, so the baseline of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states 'List all accessible GitLab projects' which is a specific verb+resource combo. It also distinguishes from the sibling tool gitlab_get_project by noting that detailed info is available there, making it easy to identify this as the listing tool.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly names an alternative: 'Use gitlab_get_project to fetch detailed info.' This provides clear guidance on when to use this tool vs. a close sibling, though it does not mention exclusions for other siblings like gitlab_list_issues or gitlab_list_mrs.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.